1. Field of the Invention
The present invention relates to an image forming system for analyzing an image which is printed on recording paper, by optically reading the image, and for feeding back to the correction in the printing.
2. Description of Related Art
In a printing apparatus in which the accuracy of the printing is required, the image which is printed on the recording paper by the printing apparatus is optically read by a separate scanner and the read image is analyzed to correct the parameters used in the printing.
In Japanese Patent Application Publication No. 2012-170002, the technology in which an image is corrected so as to prevent a thin line from becoming thicker when an original is copied by a copy machine, is disclosed. In this technology, by reading a test chart in which thin lines are printed, with a scanner to analyze the test chart, the blurred edge which is caused when the original is read with the scanner, is detected. The correction parameter for thin lines, which is used when the image obtained by reading the original with the scanner is printed, is selected according to the degree of blurred edge.
In the method for correcting the parameter used in the printing by optically reading the image printed on the recording paper in the printing apparatus with a separate scanner and by analyzing the read image, it is difficult to analyze the read image in consideration of the detailed operation state of the printing apparatus in the printing of the image and the printing conditions. For example, it is difficult to output the information indicating the detailed operation state of the printing apparatus, such as the detailed contents of the image correction carried out in the printing apparatus, the information indicating the positional relation between the image printed on the recording paper and the photoconductor, and the like, from the printing apparatus to an external device. Even though the above information can be output, because of the large data size of the information, large tasks for inputting the information to the device for analyzing the image are required.
For example, the step for adding the detailed information in the printing of the image to the recording paper by using a barcode or the like is required. Alternatively, as shown in FIG. 21, the step for registering the detailed information relating to the operation state of each unit of the printing apparatus in the printing of the test pattern by using the printing apparatus and the printing conditions, in the database to transmit the detailed information to the analyzing device, is required. Further, there are limitations on the feedback of the analysis result to the printing apparatus.
In particular, in case that the width or the like of thin line is corrected, a high accurate correction cannot be carried out without considering the operation state of the apparatus in the printing of the test pattern and in the reading of the test pattern.